Informatics Publishing Limited

B. Garudadwajan ¹, S. Karthikeyan ¹, S. Thiagarajan ¹

Affiliations
1 Information Centre for Aeronautics, National Aeronautical Laboratory, Kodihalli, Bangalore 560 017, IN

Abstract

A sample survey was undertaken to study the pattern of use of library documents, in specified areas, as revealed by the loan transactions over the twenty-year period 1960-1980, divided into 10 spans of 2 years each. The survey was taken up to provide an objective criterion for the management to take decisions on library collection development policies including the desirability of removing the less used library documents to a secondary shelving space and their eventual weeding out from the collection and transfer to a National depository of library documents of archival nature. The analysis presented in this case study is based on a sample of 1011 documents in the area of materials science that were circulated during the period. The 'Use factor' of a document issued atleast once during the period covered by the Survey has been statistically investigated and presented. A further attempt has been made to characterise the distribution of issue transactions of documents acquired in three specific years, i.e. 1970,1971 and 1973, fit theoretical distributions to the use frequency data, and obtain the criticality of use in each case.

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Dewashish Kumar ¹, S. N. Rai ¹, S. Thiagarajan ¹, Y. Ratna Kumari ¹

Affiliations
1 CSIR-National Geophysical Research Institute, Hyderabad 500 007, IN

Abstract

Interpretation of vertical electrical sounding (VES) data coupled with the estimation of coefficient of anisotropy (λ) in parts of Kalmeshwar taluk, Nagpur district, Maharashtra, India has yielded vital information on the characteristics of subsurface basaltic aquifers. The coefficient of anisotropy estimated at 22 sites from VES data has shown variation between 1 and 1.87, which in turn reveals the anisotropic character of the basaltic aquifers. The estimated fracture porosity from the interpreted parameters and specific conductance of groundwater within the region varies from 0.007% to ∼2%, indicating different degrees of water saturation within the basaltic flows. The interpreted true resistivity ∼10-35 Ω.m corroborates well with the zones of high porosity and λ further substantiates the presence of exploitable groundwater resources within the region.

Keywords

Anisotropy, Hard Rock Aquifers, Fracture, Porosity, Vertical Electrical Sounding.

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Dewashish Kumar ¹, S. Thiagarajan ¹, S. N. Rai ¹

Affiliations
1 Council of Scientific and Industrial Research (CSIR) - National Geophysical Research Institute, Uppal Road, Hyderabad - 500 007, IN

Abstract

Exploration of Geothermal resources is important from energy point of view. Western margin of volcanic Deccan traps, also known as Western Ghats, is characterized with the presence of numerous hot springs. The resistivity contrast for the geothermal reservoir rock and the surrounding host rock is significantly high in volcanic terrain which is the case of present study. In such cases the resistivity associated with geothermal reservoirs usually varies from <5 to 15 Ohm-m regardless of how high resistivity is outside the reservoir zone. Direct current (DC) resitivity method is proved to be more suitable method for delineation of groundwater reservoirs. The present work describes the results of electrical resistivity tomography survey carried out at four hot spring sites located at Unhavare (Khed), Tural, Rajwadi and Aravali villages of Chiplun taluk in Ratnagiri district of Maharashtra for delineation of the geothermal reservoirs and associated geological features like faults and fractures responsible for vertical movement of geothermal water with the sole purpose of harnessing geothermal energy. In addition to this, the present study is also aimed to delineate the groundwater reservoirs with normal temperature for exploration purpose to meet the local water supply demand. The interpreted results of the field data suggest the presence of two potential geothermal reservoirs at Unhavare (Khed) and one each at Tural and Aravali. Potential groundwater zones with normal temperature are also delineated for groundwater exploration at Rajwadi and Aravali sites.

Keywords

Geothermal Energy Resource, Electrical Resistivity Tomography, Deccan Traps, Hot Springs, Faults, Maharashtra.

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